The present invention relates to an ink jet printer in which ink is jetted selectively from a number of nozzles.
An ink jet printer for jetting ink from a selected one or plural nozzles to record characters, patterns, etc., on a recording sheet is advantageous in that it makes no noise while in operation and it can record data on an ordinary recording sheet at low operating cost.
In general, an ink jet printer of this type uses watersoluble ink in order to stabilize the writing operation. As a result, the printer may suffer from the difficulty that the water contained in the water-soluble ink may make the recording sheet wavy or swell it during a printing operation, as a result of which it becomes rather difficult to convey the recording sheet to the following work position.
In order to eliminate the difficulty, Japanese Unexamined Published Patent Application No. 156536/1979 has disclosed a device in which hot air is blown against the recording sheet on the platen to dry the ink. Also, U.S. Pat. No. 4,340,893 has disclosed a device in which hot air is blown against the recording sheet directly through the carriage to dry the ink on the recording sheet as soon as data is recorded on it. However, those conventional devices are still disadvantageous in that, in general, characters or patterns recorded on a recording sheet often vary in density, and sometimes they may be solid black. Hence, even if a hot air dryer is set downstream of the recording section to dry the recording sheet, it is rather difficult to sufficiently dry parts of the recording sheet having a high pixel density. As a result, wet parts of the recording sheet may be brought into contact with the back side of the following recording sheet, thus spoiling the recorded image. Also, parts of the recording sheet swelled and buckled by the ink may be brought into contact with the printing head, thus wearing the latter.